River Condition Assessment for BNG

Biodiversity Net Gain (BNG) is now required by local planning authorities for all proposed developments. Under this requirement, if a project’s boundary line contains a river or stream, regardless of whether it is directly affected by the proposed activities, there will be an obligation to achieve mandatory Biodiversity Net Gain (BNG) specifically for rivers and streams.

River condition assessments (RCA) are essential to assess the potential impact of the proposed development. These assessments are often requested by local planning authorities during the planning application process. A development may be delayed or refused planning permission until mitigation measures are put in place.

What is the river condition assessment process?

Here are key components of a river condition assessment for BNG:

  1. Baseline Assessment: A Modular River Physical (MoRPh) field survey is conducted to collect information on vegetation, sediments, and water-related features. A river type desk-based survey is also carried out. This desk study is used to gather existing data and information related to the site area.
  2. Impact Assessment: Assessing the potential impacts of the proposed development or land use change on the river ecosystem. This includes considering direct impacts (e.g., habitat loss, pollution) as well as indirect impacts (e.g., changes in hydrology, sedimentation).
  3. Biodiversity Net Gain Calculation: Calculating the expected change in biodiversity resulting from the proposed project using the Biodiversity Metric 4.0. This involves comparing the baseline biodiversity of the river or stream with the predicted biodiversity after implementation of the project, accounting for any mitigation or enhancement measures.
  4. Mitigation and Enhancement Measures: Identifying and implementing measures to mitigate any negative impacts and enhance biodiversity within the river or stream. This may include river restoration for habitats, installation of fish passages, and implementation of erosion control measures.
  5. Compliance and Reporting: Ensuring compliance with regulatory requirements for Biodiversity Net Gain and providing transparent reporting on the outcomes of the river condition assessment, including the predicted biodiversity net gain and effectiveness of mitigation measures.

By conducting a thorough river condition assessment for Biodiversity Net Gain, developers and planners can ensure that development projects contribute positively to the conservation and enhancement of rivers, thereby meeting BNG requirements.

How can Collington Winter assist?

Our team of ecologists and land managers have helped numerous clients with river condition assessments for planning and development.

We can also assist with biodiversity net gain by providing: 

Please get in touch if you would like further information about RCA methods. We are happy to offer free CPD sessions on the BNG principles and how we can help your schemes achieve this.

Our Ecology Director, Olivia Collington, holds a Natural England license. If you would like to find out more about the services we provide, feel free to contact us using the details below.

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